Known derivatives of anthracycline antibiotics exhibit improved pharmacological properties as compared with the parent antibiotics--F. Arcamone, Canc. Chem. Rep. 1975, 6/No 2/,23. F. Arcamone, J. Med Chem. 1974, p. 17 and 33 s., Proc. of the 11th Intern. Cancer Congress Florence 1974.
The disadvantages of the described compounds as well as the native antibiotics and their structural analogues are their toxicity, particularly cardiotoxicity, and their unstability. These cause lowering of the efficacy of therapy and their solubility in water.